1. Swiss Federal Research Institute WSL Zuercherstrasse 111 8903 Birmensdorf Switzerland
2. Karlsruhe Institute of Technology Institute of Meteorology and Climate Research – Atmospheric Environmental Research (IMK‐IFU) 82467 Garmisch‐Partenkirchen Germany
3. ETH Zurich Institute of Agricultural Sciences Universitaetsstrasse 2 8092 Zurich Switzerland